Artificial Crystal Research Center, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 215 Chengbei Road, Jiading, Shanghai 201800, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Artificial Crystal Research Center, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 215 Chengbei Road, Jiading, Shanghai 201800, China.
Ultrasonics. 2020 Dec;108:106175. doi: 10.1016/j.ultras.2020.106175. Epub 2020 May 24.
The Finite element modeling (FEM) simulation and comparison of electroacoustic properties for alternating current poling (ACP) phased arrays and direct current poling (DCP) phased arrays were investigated. The simulated electrical impedance reveals that the effective working bandwidth of ACP phased arrays is wider than that of DCP phased arrays as a whole. Besides, the ACP phased arrays have a higher effective electromechanical coupling coefficient k compared to DCP arrays, which indicates that higher electromechanical conversion capacity is obtained. The average value of the ratio of longitudinal displacement R for ACP phased arrays is larger than that of DCP arrays, indicating that the longitudinal transmission efficiency of acoustic energy can be enhanced by using the ACP method. The simulation results of crosstalk are consistent with the results of vibration modal analysis. The coupling effect of transverse vibration for ACP phased arrays is weaker than that of DCP arrays, leading to reduce the interaction between the adjacent elements. The crosstalk of the ACP arrays is -11.87 dB, 0.91 dB lower than that of DCP arrays. The pulse-echo response of ACP phased arrays is 7.2% broader -6 dB bandwidth, 0.79 dB higher relative sensitivity compared to the DCP phased arrays, which prove that the longitudinal resolution and penetration depth of the ultrasonic imaging can be improved by using the ACP arrays. Besides, the consequences of the beam profile illustrate that the maximum acoustic pressure of ACP arrays is 13.8% higher than that of DCP arrays and the directivity of ACP array is slightly better than that of DCP arrays.
交流极化相控阵和直流极化相控阵的电声性能的有限元建模（FEM）模拟和比较。模拟的电阻抗表明，交流极化相控阵的有效工作带宽整体上比直流极化相控阵宽。此外，交流极化相控阵的有效机电耦合系数 k 比直流极化相控阵高，这表明可以获得更高的机电转换能力。交流极化相控阵的纵向位移比 R 的平均值大于直流极化相控阵，这表明可以通过使用交流极化方法来提高声能的纵向传输效率。串扰的模拟结果与振动模态分析的结果一致。交流极化相控阵的横向振动的耦合效应比直流极化相控阵弱，从而减少了相邻单元之间的相互作用。交流极化相控阵的串扰为-11.87 dB，比直流极化相控阵低 0.91 dB。交流极化相控阵的脉冲回波响应的-6 dB 带宽宽 7.2%，相对灵敏度高 0.79 dB，与直流极化相控阵相比，这证明了可以通过使用交流极化相控阵来提高超声成像的纵向分辨率和穿透深度。此外，波束轮廓的结果表明，交流极化相控阵的最大声压比直流极化相控阵高 13.8%，并且交流极化相控阵的指向性略优于直流极化相控阵。
